Powder Brown Tang (Acanthurus nigricans)

Acanthurus japonicus

Richard Zerpe / Flickr / CC By 2.0

A popular fish, but one that requires careful maintenance, the Powder Brown Tang is best housed as the only Tang present in an aquarium. The Powder Brown does best in a large tank with plenty of potential "houses" or places to duck into when it feels threatened. Although the similar Goldrim or Whitecheek Tang (Acanthurus nigricans) is also delicate, it is somewhat more durable.

Breed Overview

Common Names: Powder Brown Tang, Powder Brown Tang, Powder Brown Surgeonfish, Powder Black Surgeon, Japan Surgeonfish, White-nose Surgeonfish, White-Faced Surgeonfish

Scientific Name: Acanthurus japonicus

Adult Size: 8.3 inches

Life Expectancy: 7+ years


Family Acanthuridae
Origin Western Pacific.
Social Peaceful except with other Surgeonfish
Tank Level All levels
Minimum Tank Size 100 gallons
Diet Herbivore
Breeding Group spawner
Care Difficult
pH 8.1–8.4.
Temperature 72–78 degrees Fahrenheit

Colors and Markings

The Powder Brown Tang has a black dorsal fin; its anal fins are edged in blue; its dorsal fin is edged in red, and it has yellow stripes along its body. Its face is mostly white. With all this color, however, its body is the dark brown color for which it is named. If your Powder Brown Tang suddenly sports a yellow color on the rear part of its body, there's a good chance it has been frightened or startled.

Powder Brown Tang are similar in appearance to the Whitecheek Surgeonfish Acanthurus nigricans, and it is possible that your fish is actually a Whitecheek rather than a Powder Brown as they are often sold under the same name. One difference between the two is the amount of white on their faces (the Whitecheek, oddly, has less white on its face than the "official" Powder Brown Tang).  

Origin and Distribution

The Powder Brown Tang is widely distributed across the Indo-West Pacific; it can be found in the waters of southern Japan, Taiwan; Indonesia, the Philippines, the Hawaiian Islands, and New Caledonia. Its name, japonicus, refers to the fact that it's often found off the coast of Japan.


Powder Brown Tang is a relatively peaceful Surgeonfish and can be kept in a reef or community tank provided the tank is large enough (they need a great deal of space to move, and can be very messy with their food). This species can be a good tankmate for a wide range of fish or any size, even with smaller semi-aggressive fish; some potential tankmates include Clownfish, Goby, Blenny, Anthias, and Fairy Wrasses. 

There are a few exceptions to this rule: like most Surgeonfish, Powder Brown Tangs can be aggressive toward others of its own genus and are easily stressed by more aggressive fish. Thus, while it's fine to keep your pet with many other fish and marine animals, it's best to keep just a single Surgeonfish in the tank. Be sure to avoid aggressive fish such as Triggers, Lionfish, Puffers, and Grouper.

Powder Brown Tangs are excellent reef fish, as they graze on algae but will rarely damage coral or attack invertebrates. They can cause some stress to invertebrates, however, as their algae-nibbling can lead to minor damage to coral and clams. These issues can often be handled by ensuring that your tang is fed a plentiful, nutritious diet.

Power Brown Tang Habitat and Care

Powder Brown Tang are caught in the wild and can suffer from a wide range of issues as a result. Stress, parasites, and disease are all possible. It's thus best to select a fish that has been in captivity for a few months and is visibly at ease and eating in its tank. Once you select a Power Brown Tang, you'll need to prepare its environment with care as it's a fragile fish that can be easily stressed.

Your new pet's tank should be as large as possible (125 gallons is ideal), and it should be a stable environment; a brand new tank is likely to create challenges for your Tang. Provide a sandy substrate, so the Tang can enjoy blowing the sand with their mouths while searching for food. Decorate the tank with nooks, crannies, reef elements, and plants, leaving plenty of open space toward the top of the tank. Choose a high-performing filtration system, and be sure there is a strong water movement to provide excellent oxygenation. Avoid using activated carbon which has been linked to head and Lateral Line Erosion in Tangs.

It's a good idea to keep the tank at a relatively low temperature (under 78 degrees Fahrenheit), as this serves several functions. First, lower temperatures mean more oxygen for your Tang. Second, Tangs tend to sicken in temperatures between 79 and 83 degrees.

The "sword", "spur" or "scalpel" at the base of the tail of the Powder Brown Tang is not as large or dangerous as it is with some other Surgeonfish, such as the Naso Tang (Naso lituratus) or the Achilles Tang (Acanthurus achilles) however they are still large enough and sharp enough to inflict a serious wound so be cautious when handling this fish.

Unlike some of the sturdier Surgeonfish such as the Naso Tang, the Powder Brown is susceptible to gill and fin ammonia burns. Usually caused by excess ammonia accumulation during collection from the ocean or during shipping, "ammonia burns" to the gills can be quite serious and eventually fatal in the more serious cases. When purchasing a Powder Brown Tang, have the seller show you that the fish is indeed eating (the first sign of problems with a fish is lack of appetite) and what it is eating.

Powder Brown Tang Diet

Primarily a herbivore that will graze on filamentous micro and some types of smaller fleshy macroalgae, the Powder Brown should be fed at least 3 times a day on a diet of frozen and dried fares suitable for herbivores that contain marine algae and Spirulina (blue-green algae). Zucchini, broccoli, leaf lettuce, and nori (dried seaweed) can be offered to supplement its diet. Meaty fare should be offered several times per week to help provide extra protein. A veggie clip with dried seaweed hung from the side of the tank makes it easier to keep a good supply of macroalgae available to the Powder Brown Tang.

Breeding the Powder Brown Tang

Powder Browns are group spawning fish; their eggs are fertilized at the same time that they are released, and they float along the surface of the water. It is extraordinarily difficult to care for the larval Tangs, and as a result virtually all captive Power Brown Tangs are wild-caught.

More Pet Fish Breeds and Further Research

If you’re interested in learning more about Tangs, check out:

Otherwise, check out all of our other saltwater pet fish breed profiles.